What Evidence to Attach to a Letter of Demand for Unpaid Invoices

A letter of demand without evidence is just a polite request. The evidence you attach proves you have a legitimate claim, proper records, and the willingness to take the matter further if needed.

This guide lists what evidence strengthens a letter of demand for an unpaid invoice, how to reference each document, and what to do when records are incomplete.

The core documents every demand needs

These documents prove the debt exists and remains unpaid.

Original tax invoice The invoice that created the debt must show:

• Your business name and ABN
• The debtor’s name and contact details
• Invoice number and date
• Description of goods or services supplied
• Total amount payable
• Payment terms (e.g. “Payment due within 14 days”)

If you issued multiple invoices, attach all unpaid ones. Reference them by invoice number and date: “Invoice #1234 dated 15 March 2024 for $2,500 remains unpaid.”

Proof of delivery or completion Evidence that you provided what you invoiced for:

• Signed delivery docket
• Email confirmation from the client acknowledging receipt
• Photos of completed work
• Signed job completion form
• Tracking information showing delivery to the correct address

Without this, the debtor can argue they never received the goods or that the work was never done. Reference it clearly: “As evidenced by the signed delivery docket dated 18 March 2024 (Annexure B), the goods were received by your employee John Smith.”

Payment terms or contract Any document setting out when payment was due:

• Written service agreement or purchase order
• Quote or proposal that was accepted
• Email exchange confirming terms
• Your standard trading terms if provided before the work

If payment terms were verbal, state that in the letter: “As agreed verbally on 10 March 2024, payment was due within 7 days of invoice.” If you have an email or text message confirming the conversation, attach it.

Supporting documents that strengthen your claim

These documents make your claim harder to dispute.

Prior correspondence chasing payment Any emails, letters, or text messages where you previously asked for payment. This shows you gave the debtor a reasonable opportunity to pay and that you have been patient.

Attach them as a bundle and reference them: “Despite reminders sent on 1 April, 15 April, and 30 April 2024 (Annexure D), no payment has been received.”

Bank statements or payment records If the debtor made partial payments, attach:

• Bank statements showing what was paid and when
• Payment reference numbers
• Outstanding balance calculation

This prevents arguments about what has already been paid. Reference it: “You paid $1,000 on 5 April 2024, leaving a balance of $1,500 outstanding.”

Evidence of agreed variations or extras If the invoice includes additional work or price changes:

• Emails approving the variation
• Signed variation forms
• Text messages confirming the extra work

Without this, the debtor may argue the invoice amount is inflated. Reference clearly: “The additional $800 for waterproofing was approved by you via email on 20 March 2024 (Annexure F).”

Statutory declarations or witness statements If the debtor is likely to dispute the facts, consider attaching:

• A statutory declaration from yourself summarising the transaction
• A witness statement from an employee who dealt with the debtor
• A statement from a third party who can verify delivery or completion

These carry weight because they are made under penalty. Reference them: “The facts are set out in my statutory declaration dated 10 May 2024 (Annexure G).”

How to reference evidence in the letter

Reference each piece of evidence specifically in the body of the letter using annexure labels.

Use a consistent annexure system Label each document as Annexure A, B, C, etc., in the order you mention them:

“On 15 March 2024, I issued Invoice #1234 for $2,500 (Annexure A). The goods were delivered on 18 March 2024, as confirmed by the signed delivery docket (Annexure B). Payment was due within 14 days, making the due date 1 April 2024. Despite reminders sent on 1 April, 15 April, and 30 April 2024 (Annexure C), no payment has been received.”

This makes it easy for the recipient (and later, a tribunal) to match each claim to the supporting document.

State what each document proves Spell out the relevance:

“Annexure D is a copy of the service agreement signed by you on 10 March 2024, which confirms that payment was due within 7 days of invoice.”

“Annexure E is a screenshot of the email you sent on 20 March 2024 approving the additional $800 for waterproofing.”

Keep the originals Attach copies to the letter, but keep the originals. If the matter goes to tribunal, you will need to produce the originals.

What to do when evidence is missing

Sometimes you do not have perfect records. Here is how to handle common gaps.

No written contract If the agreement was verbal, state the terms clearly and refer to any conduct that supports those terms:

“Although no written contract was signed, you accepted my quote via email on 10 March 2024 (Annexure A), and I commenced work immediately. The quote specified payment within 14 days of invoice.”

No proof of delivery If you have no signed docket but the debtor used the goods or services, state that:

“Although no delivery docket was signed, you have been using the equipment since 18 March 2024, as evidenced by your email of 25 March 2024 requesting a user manual (Annexure C).”

No prior reminders If this is your first contact chasing payment, state the facts:

“The invoice was issued on 15 March 2024 with payment due on 1 April 2024. No payment has been received, and this letter serves as formal demand.”

Partial records If you have some evidence but not all, attach what you have and explain the rest:

“Attached is Invoice #1234 (Annexure A) and the signed quote (Annexure B). The goods were delivered by courier on 18 March 2024; I have requested delivery confirmation from the courier company and will provide it if this matter proceeds further.”

What happens if the debtor disputes the evidence

If the debtor replies claiming the invoice is incorrect, the goods were defective, or the work was not completed, you will need to respond with additional evidence. Keep all correspondence and consider:

• Obtaining a statutory declaration from yourself or a witness
• Getting an independent assessment (e.g. a building inspector’s report)
• Requesting a mediation session before filing a tribunal application

If the dispute is genuine and complex, seek advice from a qualified Australian lawyer. But if the debtor is simply stalling without valid grounds, the evidence you attached to the demand letter will support your case when you file a tribunal application.

Final checklist before sending

Before you send the letter, confirm:

• [ ] Original invoice attached and referenced
• [ ] Proof of delivery or completion attached
• [ ] Payment terms or contract attached
• [ ] All prior correspondence attached (if any)
• [ ] Each annexure labelled clearly (A, B, C, etc.)
• [ ] Each annexure referenced in the body of the letter
• [ ] Originals retained in your files
• [ ] All documents legible and complete

A well-evidenced letter of demand is more likely to result in payment and sets you up for success if you need to take the matter to tribunal.

How Claim Done prepares your evidence bundle

ClaimDone generates your letter of demand with all evidence properly referenced and formatted. Upload your invoices, contracts, delivery records, and correspondence during the intake process. The system reviews each document, drafts the letter with specific annexure references, and sends it automatically to the debtor as a single PDF with all attachments. You receive a copy for your records, and the evidence bundle is preserved if the matter escalates. Start your letter of demand now at claimdone.com.au/services/letter-of-demand.

Frequently Asked Questions

Do I need to attach the original invoice or can I just describe it?

Always attach a copy of the original invoice. Describing it is not enough. The debtor (and later, a tribunal) needs to see the actual document showing the amount, date, payment terms, and what was invoiced. Without it, your claim has no foundation.

What if I have no proof of delivery because it was a service, not goods?

Attach evidence that the service was completed: photos of the finished work, a signed completion certificate, an email from the client acknowledging the work, or even a review they left. If you have nothing, state in the letter when and where the service was performed and refer to any conduct showing they accepted it.

Can I attach text messages as evidence?

Yes. Take screenshots showing the date, time, and phone number, and save them as a PDF. Text messages are typically admissible evidence in Australian tribunals, especially for proving agreements, approvals, or acknowledgments of debt.

How many reminders should I attach?

Attach all of them. If you sent one reminder, attach it. If you sent ten, attach them all as a bundle. This shows you gave the debtor multiple opportunities to pay and demonstrates your patience and professionalism.

What if the debtor claims they never received the letter of demand?

Send it via registered post or email with read receipt, and keep proof of sending. If you use Claim Done, the letter is sent automatically via email and tracked, so you have a record of delivery. If the debtor ignores it, that record becomes evidence of their refusal to engage.